Parachute releasing means



Allg. 10, 1954 H W KLAS PARACHUTE RELEASING MEANS 2 Sheets-Sheet 1 Filed Sept. 24, 1946 4 373mm HWKMS Aug. 10, 1954 H. w. KLAS PARACHUTE RELEASING MEANS 2 Sheets-Sheet 2 Filed Sept. 24, 1946 u Z w 7 2 gmc/ww- WIfZaS Patented Aug. I0, 19.54'

UNITED STATES ENT OFFICE l Claims. (Cl. 244-138) (Granted under Title 35, U. S. Code (1952),

sec. 266) This invention relates generally to means for releasing a parachute from a load carried thereby such, for example, as mines, torpedoes, rescue equipment and the like, and more particularly to parachute release means which operate in response to the impact of the load with the surface of the target area.

Various devices heretofore employed for releasing a parachute from its load upon impact with the target area have normally comprised an inertia responsive element for shearing or removing' a pin adapted to couple the parachute to the load. Such devices have not been found to be entirely satisfactory under all conditions of service for the reason that the force of inertia acting on the inertia element may be insufiicient to shear the coupling pin when the load strikes the surface of the target area at an oblique angle therewith or when the load enters a body of water at a relatively low velocity.

The foregoing difficulties of the prior art devices, when employed for use with marine mines and like devices, have been obviated by the parachute release mechanism for a marine mine disclosed and claimed in my copending application for Parachute Release Means, Serial No. 603,100, led July 3, 1945 wherein an electroresponsive detonator is energized by a sea battery as the mine enters the water and the coupling pin is forcibly ejected to disconnect the parachute from the mine by the force of the explosion as the detonator is fired.

According to the arrangement of the present invention, the detonator of the release mechanism of the aforementioned application is energized by a circuit under control of an inertia switch responsive to relatively weak inertia forces whereby the parachute release mechanism may be caused invariably to release the parachute from its load regardless of whether the load strikes upon land or sea and substantially independently of the angle of impact with the surface thereof. As the mine strikes the surface of a body of water or of the earth, whichever the case may be, the impact causes a metallic ball confined within a cylindrical tube to be moved forcibly past a yieldable detent into circuit closing relation with a pair of switch elements forming a part of the aforesaid circuit and disposed in the bottom of the tube, the detent normally serving to prevent such movement of the ball.

Means releasable upon launching the load from an aircraft is also provided to prevent movement of the ball into actuating engagement 2 with the detent in response to shocks received by the release mechanism during handling or transportation thereof.

Olne of the objects of the present invention is the provision of new and improved means for releasing a parachute from its load wherein the release is effected by ring an explosive charge when the load strikes the surface of the target area.

Another object is to provide a new and improved parachute releasing mechanism adapted to operate on relatively weak inertia forces resulting from impact of the parachute load with the surface of the target area.

Another object resides in the provision of a parachute releasing mechanism in which the parachute is released from its load by the eX- plcsion of a charge and in which the charge is fired under control of an inertia switch responsive to the impact of the load with the surface of the target area substantially independently of the velocity of the load and the angle at which it strikes the surface.

A further object is to provide an inertia responsive parachute release mechanism having means for preventing actuation of the mechanism in response to shocks received thereby during handling and transportation.

Still other objects, features and advantages of the present invention are those implied from or inherent in the novel construction, combination and arrangement of parts as will become more fully apparent from the following detailed description of a preferred embodiment of the invention, reference being had to the accompanying drawings in which:

Fig. 1 is a view in elevation, partly in section and partly broken away, of a mine and a parachute pack suitable for use with the parachute release mechanism of the present invention;

Fig. 2 is an enlarged plan view partly in section and partly broken away of the release mechanisrn taken along the line 2-2 of Fig. 1 and showing the various elements of the release mechanism prior to actuation thereof;

Fig. 3 is an enlarged sectional View taken along the line 3 3 of Fig. l and showing the means for holding the switch ball in a safe locked position prior to launching of the mine;

Fig. 4 is a sectional View taken along the line 4 4 of Fig. 2 and showing one method of mounting the batteries and providing the electrical connections therebetween; and

Fig. 5 is a sectional view taken along the line 5-5 of Fig. 2 and showing details of the switch actuating mechanism.

Referring now to the drawings in which like numerals of reference are employed to designate like parts throughout the several views and more particularly to Fig. l, there is shown thereon a parachute indicated generally by the numeral I9, having a plurality of shroud lines il for establishing a connection between the parachute and the parachute releasing mechanism attached to the mine I2. The parachute I is provided with a parachute pack including a dishshaped member I3 within which the parachute is folded prior to the release of the mine from an aircraft in flight, the parachute being adapted to be withdrawn from the member in any well known manner as, for example, by a static line as the mine falls away from the aircraft.

Member I3 is supported by a washer It and a shroud keeper I5 which are secured together in any suitable manner as by the bolts I6 so as to clamp member I3 therebetween. Shroud keeper I5 has an internally threaded portion Il adapted to receive the externally threaded projection I8 of the latch body I9. The latch body I9 is provided with a transverse slot '2t adapted to receive the upstanding portion 2| of the support 22 attached to the mine I2.

Latch body i9 has a transverse cylindrical portion il having therein a central bore 34 containing a pin 24. which also passes through a bore 23 in upstanding portion 2| when the latch body is in assembled position on support 22. Pin 24 is slideably arranged in the transverse cylindrical portion 9 and is locked to the latch body I9 by shear pin 32 when the pin 2Liis in the assembled position, a suitable transverse bore 33 being provided within the pin for this purpose.

An enlarged exhaust chamber 25 is threadedly attached to the latch body I9 as at 25. The latch body preferably has a shoulder 2l' adapted to engage a complementary surface on the exhaust chamber whereby these parts may be drawn together tightly into registered engagement. rEhe exhaust chamber 25 is preferably provided with a plurality of apertures Sil in communication with the exhaust bore 28 therein to provide an escape for the gases formed by the firing of the electroresponsive detonator 3I which is received into a reduction of bore 34 in transverse portion 9.

Pin '24 is releasably locked in an initial position by the shear pin 32 arranged within opening 33 more clearly shown in Fig. 2, and is adapted to pass freely through the pin 24 and to be force-fitted within a suitable opening therefor in cylindrical portion 9.

As shown in Figs. 1 and 3, detonator 3l is secured within the detonator bore 29 by the set screw 35. Detonator bore 29 is in communication with a well 3E within the latch body I9 which provides a passageway for detonator leads 3l and 43, the latter lead being connected to an electrical terminal 38 extending within the passageway. Well 35 is in communication with the battery cavities 39 within which batteries 4S are confined as by threaded plugs 4I, these plugs serving, upon adjustment thereof, to urge the batteries into electrical contact with the terminal strip 42 and to ground one end of each of the batteries.

As may best be seen in Figs. 3 and 4, electrical terminal strip 42 is in electrical connection with detonator 3l by way of lead 3l thereof 4 whereby the detonator is adapted to be red by current from the parallel-connected batteries 40 when terminal 38 is connected to ground, as hereinafter more fully described.

Electrical terminal 42 is riveted, or otherwise secured, to insulation pieces 44 which are tted inot the merged opening of battery cavities 39, pieces 44 being secured to a base plate Gli as by screws 55.

Electrical terminal 38 projects into a vertical bore A5 in latch body le and is secured, as by a screw dl, to the lip of a cup-shaped insulation member 46 which is received into an enlargement of bore 45 and retained therein by plate 5&3 to which it may be secured as by pins S5. Plate tu encloses well battery cavities 39 and bore 45 and is secured to latch body I9 as by screws t1.

A terminal 59 is similarly secured to member 45, as by a screw 6I, and is disposed diametrically opposite to terminal 38 thereon. Terminal 5e, however, has a depending end portion 52 which engages latch body I9 to form a ground connection therewith. The other end of terminal 59, and the corresponding end of terminal 38, project diagonally within member 43 so as to be engageable yieldably by a metallic ball 38 carried slideably within bore 45 and retained therein by a plug 4S in threaded engagement with latch body I9 as at 50.

Ball 48 normally is yieldably maintained out of engagement with terminals 33 and 59, after arming pin 5i has been withdrawn, by means of a spring-loaded detent generally designated 55 and slideably received within a transverse opening 55 in communication with bore 45. Detent 54 has a conical-shaped reduced end portion 52 which is urged through reduction 56 of opening 55 into the path of the ball by a coil spring 53 which is interposed under compression between the detent and a plug 5l in threaded engagement with the latch body as at 5S, sockets preferably being provided in the enlarged end portion of the detent and in plug 5'! to serve as seats for the ends of spring 53. The shoulder between the enlarged and reduced end portions of the detent engages the shoulder formed between the opening 55 and the reduction 56 thereof, thus limiting movement of the detent into bore 45. The detent preferably is formed or" insulation material, as shown.

Arming pin 5I is secured in transverse bores 53 and 64 in the latch body and is connected to an arming wire 68 for withdrawing the pin therefrom.

The operation of the device will now be described. Let it be assumed that the mine is to be released from an aircraft in flight.

The arming wire 58 is attached to the aircraft structure so that arming pin 5I is withdrawn from the latch body I9 as the mine is released from the aircraft.

Switch ball 48 is held in the upper portion of bore 45 during descent of the mine l2 through the air by detent 54.

As the mine I2 strikes a body of water or the earth, as the case may be, the impact causes switch ball 43 to depress detent 54 against the opposing force of spring 53 suciently to permit the ball to move past the detent and connect electrical terminals 38 and 59. When this occurs, the circuit from batteries 4E) to detonator 3| is completed and the detonator is red. The force of the explosion of the detonator is directed against coupling pin 24 and forcibly ejects the pin from the latch body I9 and upstanding portion 2l of support 22 into the exhaust chamber 28, thereby disconnecting the parachute and pack from the mine, safety pin 32 being sheared during such movement of the coupling pin. Shear pin 32 has suiiicient strength to prevent the outward movement of the pin 24 in response to handling and launching forces but yields in response to the explosion of the detonator 3l.

Brieiiy stated in summary, the invention in its broader aspects contemplates the provision of a parachute release mechanism for a load adapted to be launched from an aircraft in flight in which the release of the parachute from the load is effected by ring a small explosive charge in response to the impact of the mine with the surface of a target area and in which the impact actuates a switch to complete a firing circuit for the charge, means also being employed for preventing the premature operation of the parachute releasing mechanism as a result of a shock or blow received during the handling, transportation or flight.

While the invention has been described with reference to a particular example thereof which gives satisfactory results, it will be understood by those skilled in the art, after understanding the invention, that various changes and modifications may be made without departing from the spirit and scope of the invention and it is intended, therefore, in the appended claims to cover all such changes and modifications.

This invention may be manufactured and used by or for the Government of the United States of America for governmental purposes without payment of any royalties thereon or therefor.

What is claimed as new and desired to be secured by Letters Patent of the United States is:

l, In a parachute release mechanism of the character disclosed for releasing an object from a parachute therefor as the object strikes the surface of a target area, the combination of a supporting member secured to the parachuted object, a -pin slideably arranged within said sup- -port and adapted to be moved from an initial locking position to a released position, a complementary member secured to said parachute and adapted to be locked to said supporting member by said pin when the pin is in said initial locking position, means for yieldably securing said pin in said initial position to prevent the movement of the pin to said released position in respense to a shock received by the release mechanism prior to the launching of said object, an electroresponsive explosive charge arranged within the complementary member in substantial abutting relation with one end of the pin and adapted to eject the pin from said locking position as the charge is red, and circuit means including a source of electric energy and a normally open inertia switch for ring said charge as the inertia switch is closed in response to the impact of the parachuted object with the surface of the target area.

2. In a release mechanism of the character disclosed for releasing a parachute from a load as the load strikes the surface of a target area, the combination of a pair of complementary members, the members being secured to the parachute and to the load respectively, means including a rod slideably arranged within said members for releasably locking the members together, an electroresponsive detonator arranged in proximate spaced relation with respect to one end of said rod and adapted to eject the rod forcibly from locking engagement with said members as the detonator is fired, and a firing circuit including at least one battery and a normally open inertia switch arranged within one of the members and adapted to complete the circuit between the battery and the detonator as the inertia switch closes in response to the impact of the load with the surface of the target area.

3. In a parachute release mechanism for an aircraft planted mine and adapted to release the parachute from the mine as the mine strikes the surface of a target area, the combination of a dish-shaped member within which the parachute is adapted to be packed, a fixture attached to the dish-shaped member adapted to engage the shroud lines of the parachute, a latch body secured to the dish-shaped member and having a plurality of bores therein, a fixed support secured to the mine, means including a slideable rod arranged within one of said -plurality of bores in the latch body and adapted to be received slideably by the fixed support thereby to provide a releasable locking engagement between the fixed support and the latch body, electroresponsive explosive means disposed within another one of the bores in the latch body and adapted to eject said rod from said locking engagement with the support as the explosive means is fired, a plurality of batteries arranged within the remaining bores in the latch body, and means including a normally open inertia switch for causing said batteries to lire the explosive means as the switch is closed in response to the impact of the mine with the target area.

Ll. In a mechanism of the character disclosed for releasing an aircraft planted mine from the parachute therefor as the mine strikes the surface of a target area, in combination, a fixed member secured to the mine, a complementary member secured to the parachute, a rod slideably arranged within said complementary and fixed members and adapted to be moved from an initial position providing a locking engagement therebetween to a moved position for releasing said locking engagement, a pin in shearable locking engagement with said rod to prevent movement thereof from said initial position in response to a shock received by the mine prior to planting thereof, an electroresponsive detonator within said complementary member in substantial abutting relation with one end of the rod and adapted to forcibly move the rod to said moved position thereof as the detonator is fired, means forming an exhaust chamber in axial alignment with said rod and adapted to receive the rod upon movement thereof to said moved position, a circuit including a plurality of batteries arranged within the complementary member for firing the detonator when the circuit is completed thereto, and a normally open inertia switch for completing said circuit between the batteries and detonator as the switch is closed and including an electrically conducting ball adapted to be moved to close the switch in response to the impact of the mine with the surface of the target area.

5. In a mechanism of the character disclosed for releasing a parachute from a mine when it strikes the surface of a target area, the combination of a latch body secured to the parachute, a complementary member secured to the mine, a latch moveably arranged within the latch body and initially in locking engagement with the complementary member, an electroresponsive detonator within the latch body for forcibly ejecting the latch from said locking engagement as the deton- 7 ator is fired, a source 'of el'eetri'czenergy 4mithin the latch-body, and meansfor 'causinguthe saurce f energy to iire=thedetonator-in responseitot'he impact 01"..the mine .vzth-theitarget: area.

Ve. In a mechanism fof the:character disclosed for releasing a mine 'from ia parachute uponimpact of the mine with-.the surfaceaofltnetarget area, the combination .ofra latcling;meln'her secured to the parachute; acomplementaryzmember secured to the Vruine, .means `for yieldably/maintaining the latching member :inf locking :engagement with' the complementary amember, ian electroresponsive detonator. associated-:withthe' latching member and adapted .to .force the latching member out of locking*engagementwithithetcompiementary :member .as .sthe 'detonator is ined, ra normally open .circuit for :firing :the detonator, said circuitv including alpair .ofaspaeedzterminala an electrically conductinglinertiaielement adapted to bridge said'terminals fand thereby '.close the circuit, and 1a spring-biased datent :interposed between the terminals 'and the inertia :element for preventing movement of @the element into bridging engagement lwith :the :..t-erminals until the element is movedfoi'ciblypast theadetent Yin response to the impact of :the mine with-:the target.

7. A device of the character .disclosedgfor "releasing a parachute lfrom ailoadias the;load:strikes the surface =of a target-arearcomprisingalpair 0l" eomplementar-y members secured Atothe :parachute and to the load respectively, amovable pin for releasably locking Vsaid `members 1together, an electroresp'onsive"explosiveimeans for forcibly moving said `pin ifrom locking ."engagement with isaid members :when vthe Aexplosive means is :.red, a ycylindrical .'member 'vertically arranged' within .oneftofssad :complementary members, aimovable inertia-:mass initially arranged Within the upper .portion of said/:cylindrical member, -ra .ring `circuit :for l;said .explosive `means including arssource -Lof power r and a pair lof l terminals .arranged in mutually spaced relation at the lower @portion :of said cylindrical lmember and adapted '.to Ydetcmatesaidiexplosive means when the terminals are bridged Tiby. said mass ras 'the masszmoves tof ailower; portieri of said: cylindrical member, and; a: spring-urged .'detent arranged betweemsaid inertia mass and said terminals for preventngmovementmf thermass: fromthe upper portionsoffsad cylindricalmember until '.themass isforciely moveftpast the .1detent.in;response to the .,impactof fthe load -wth the surface 'of .the target-area.

.References Cited .in the Aile 4of this patent UNITED STATESPATENTS Number Name Date 1,709,264 'Holt Apr.16, 1929 I'2,118,603 lHailey ?May24, 1938 2,415,686 Deirvvil'er .'Feb. 4, 194'?I 2,42,746 :Heidman May 20, 1947 2,458,478 'Maneval Jan. 4, 1949 FOREGN :PATEN TS Number Country Date 305,015 Germany 'Nov, 1, 1921 

